The placement of images on ceramic tile is commonly accomplished with decals, pad printing or screen printing. These decorating techniques tend to be limited to flat or less complex shapes in the case of decals, the image is commonly kept away from the edge of the tile because it is difficult to stretch a decal.
In the case of pad printing, a form must be made for each shape to provide a transfer. This may work for some basic shapes but the more complex the shape, the more difficult it is to decorate it. Also, each transferred image is exactly the same.
Screen printing can be used to put a design on ceramic tile but it only works for flat surfaces. This means that the beveled areas of the surface remain undecorated. All of the above processes do yield a 100% ceramic article but each has its limitation.
Japanese Patent Application S59-258802, filed by Dai Nippon Printing Co., Ltd. and Cubic Engineering Co., Ltd. on Dec. 5, 1984 and published Jun. 21, 1988 describes the use of the transfer process described in Nakanishi U.S. Pat. No. 4,010,057, Arai et al. U.S. Pat. No. 4,229,239 and Nakanishi U.S. Pat. No. 4,436,571, to print organic inks on all types of complex shapes. These U.S. patents are incorporated by reference.
The Japanese patent, application describes applying a thin coat of oil to the ceramic article prior to transferring the ceramic ink to the ceramic article. However, the japanese patent application clearly teaches firing the oiled ceramic article prior to transferring the ceramic ink. The present inventors have found that such a process in which the oil is burned off prior to printing, will adhere a ceramic ink to a ceramic article only if less than twenty percent of the surface area is printed. If the process is used to print greater than twenty percent of the surface area, the ink will tend to wash off during the rinsing step prior to firing of the printed article.